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Old 01-16-2010, 08:58 PM   #1
ohm
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Member#: 178468
Join Date: Apr 2008
Location: Somerset, NJ
Vehicle:
2007 UGM STI
IAG Built

Question Datalog - Knock Correction - Dirty MAF Sensor

Figured I would do some data logging today to check for anything strange. I noticed some negative values related to knock correction, and was wondering if this is shift knock or the knock sensor picking up false knock of some kind. I am hearing that negative KC values are acceptable in the lower RPMs, but at WOT it can be cause for concern.

I will add that the car is running great with no signs off any issues. I have an AEM wideband that reads 11.6 at WOT, and the car holds boost fine.

These logs were taken from 3rd-4th-5th gear. Any comments on the KC are welcome. Thanks.

Log 1
Code:
RPM	LOAD DAM	IADV	KC	TP	Boost	AFR	IDC	MAF	MAFV	VS
2638	0.8	1	33.5	0	36.06	-1.45	12.88	9.58	73.54	2.8	31.69
2755	1.76	1	18.5	0	99.96	1.89	15.07	17.33	83.46	2.74	32.31
2839	2	1	15	-1.4	99.96	3.48	12.19	19.91	97.11	2.96	32.93
2924	2.22	1	15.5	-1.4	99.96	5.37	11.5	19.64	112.13	3.14	32.93
3100	2.41	1	16	-1.4	99.96	7.83	12.88	23.4	124.64	3.26	33.55
3260	2.66	1	16.5	-1.05	99.96	10.88	12.88	27.59	152.89	3.48	36.04
3468	3.14	1	13	-2.45	99.96	15.95	11.15	40.5	189.88	3.84	36.04
3741	3.85	1	12	-2.45	99.96	22.19	11.15	54.8	270.44	4.18	39.15
4054	4.15	1	12.5	-2.45	99.96	22.19	11.15	60.61	281.31	4.26	39.15
4427	4.08	1	14.5	-2.1	99.96	22.19	11.15	62.72	292.42	4.3	44.12
4757	3.98	1	15.5	-2.1	99.96	22.19	11.15	67	317.05	4.4	49.09
5034	3.98	1	16.5	-2.1	99.96	22.19	11.15	71.87	347.06	4.48	49.09
5334	4.1	1	17.5	-1.75	99.96	22.19	11.15	74.77	350.22	4.56	55.92
5639	3.94	1	18	-1.75	99.96	22.19	11.15	76.49	370.05	4.64	55.92
5943	3.78	1	19	-1.75	99.96	22.19	11.15	77.91	379.67	4.6	61.52
6243	3.7	1	19.5	-1.75	99.96	22.19	11.15	80.28	377.74	4.6	67.73
6454	3.46	1	-12.5	0	32.93	14.94	11.15	58.44	208.34	3.74	67.73
5513	0.26	1	26.5	0	16.07	-8.41	11.27	8.15	36.75	2.3	72.7
4612	2.04	1	21.5	0	99.96	9.28	12.53	42.46	190.6	3.88	77.05
4910	3.92	1	18	0	99.96	22.19	11.15	76.09	353.4	4.54	77.05
5162	4.24	1	18.5	0	99.96	22.19	11.15	76.72	361.71	4.52	80.16
5300	4.12	1	19	0	99.96	22.19	11.15	76.15	357.23	4.58	80.16
5446	4.06	1	19.5	0	99.96	22.19	11.15	76.16	352.14	4.58	82.64
5644	3.96	1	19.5	0	99.96	22.19	11.15	77.17	366.2	4.56	85.75
5769	3.9	1	20	0	99.96	22.19	11.15	76.38	366.83	4.58	85.75
5896	3.83	1	20.5	0	99.96	22.19	11.15	77.29	377.74	4.6	90.1
6035	3.82	1	20.5	0	99.96	22.19	11.15	80.61	392.49	4.66	94.45
6180	3.74	1	21	0	99.96	22.19	11.15	79.17	380.31	4.62	94.45
6317	3.62	1	22	0	99.96	22.19	11.15	79.23	373.89	4.58	98.18
5947	1.73	1	-14.5	0	11.76	-5.08	11.15	29.94	57.09	2.18	98.18
5381	0.26	1	29	0	16.07	-9.14	11.15	8.01	33.85	2.3	101.9
5501	2.47	1	20	-1.4	99.96	13.49	11.85	63.71	294.76	4.32	103.15
5485	4.19	1	18	-1.4	99.96	22.19	11.15	83.81	393.75	4.64	103.15
5618	4.14	1	18.5	-1.4	99.96	22.19	11.15	80.55	384.8	4.68	105.63
5750	4	1	18.5	-1.4	99.96	22.19	11.15	79.93	374.53	4.64	105.63
5864	3.93	1	19	-1.05	99.96	22.19	11.15	78.62	367.48	4.6	106.25
5660	3.05	1	-12.5	0	13.33	0.29	11.15	29.77	86.94	2.94	109.98
5038	0.27	1	9	0	11.37	-9.72	11.15	6.32	18.8	1.82	109.98
4426	0.26	1	9	0	10.98	-10.59	11.39	5.73	21.64	1.8	111.23
4394	0.25	1	9	0	10.58	-11.02	12.19	5.64	16.72	1.74	112.47
4357	0.24	1	24	0	10.58	-11.31	11.96	5.56	18.8	1.76	112.47
Log 2
Code:
RPM	LOAD DAM	IADV	KC	TP	Boost	AFR	IDC	MAF	MAFV	VS
4079	4.09	1	14	-1.05	99.96	22.19	11.15	62.2	304.88	4.24	40.39
4465	4.02	1	15.5	-1.05	99.96	22.19	11.15	64.48	291.21	4.34	44.12
4765	3.91	1	17	-0.7	99.96	22.19	11.15	69.39	314.01	4.36	49.09
5072	4.02	1	17.5	-0.7	99.96	22.19	11.15	73.87	327.55	4.48	49.09
5438	3.88	1	18.5	-0.7	99.96	22.19	11.15	75.32	362.99	4.58	55.3
5758	3.83	1	19.5	-0.35	99.96	22.19	11.15	77.91	375.17	4.58	62.14
6030	3.77	1	20	-0.35	99.96	22.19	11.15	78.51	369.4	4.6	62.14
6299	3.64	1	21	-0.35	99.96	22.19	11.15	78.1	382.88	4.66	67.73
6520	3.55	1	22	-0.35	99.96	22.19	11.15	81.63	395.66	4.66	67.73
6145	1.25	1	-15	0	10.58	-6.82	11.39	16.77	21.64	1.7	73.94
5770	0.71	1	38	0	40.38	0	11.61	25.19	127.81	3.6	77.67
5157	3.33	1	19.5	0	99.96	19.72	11.27	70.37	340.08	4.5	77.67
5248	4.23	1	17	-1.4	99.96	22.19	11.15	78.85	370.68	4.58	81.4
5407	4.04	1	17.5	-1.4	99.96	22.19	11.15	76.26	354.68	4.56	83.26
5549	3.91	1	18	-1.4	99.96	22.19	11.15	74.81	357.23	4.56	83.26
5693	3.81	1	18.5	-1.4	99.96	22.19	11.15	75.63	361.06	4.58	86.99
5851	3.77	1	19.5	-1.05	99.96	22.19	11.15	76.25	377.74	4.62	90.72
6046	3.75	1	19.5	-1.05	99.96	22.19	11.15	77.14	377.74	4.6	90.72
6106	3.75	1	20	-1.05	99.96	22.19	11.15	77.87	377.1	4.6	95.69
6289	3.64	1	21	-0.7	99.96	22.19	11.15	77.83	377.1	4.62	95.69
6378	3.55	1	21.5	-0.7	99.96	22.19	11.15	77.73	375.81	4.6	99.42
6494	3.48	1	21.5	-0.7	99.96	22.19	11.15	78.31	375.81	4.52	103.15
5950	0.55	1	9	0	11.37	-8.41	11.27	8.75	14.38	1.52	103.15
5439	1.68	1	32	0	45.86	5.08	12.42	41.29	191.67	3.88	105.01
5619	3.8	1	19.5	0	99.96	22.19	11.15	82.53	380.31	4.62	106.88
5749	4.07	1	20	0	99.96	22.19	11.15	81.34	382.86	4.62	106.88
5840	3.88	1	20	0	99.96	22.19	11.15	78.69	371.96	4.6	108.12
5933	3.8	1	20.5	0	99.96	22.19	11.15	77.24	368.75	4.62	108.12
6002	3.74	1	20.5	0	99.96	22.19	11.15	77.04	372.6	4.54	110.6
5517	0.63	1	8.5	0	10.98	-8.27	11.15	10.41	29	2.04	113.71
4943	0.26	1	9	0	11.37	-10.59	11.15	7.33	22.3	1.84	113.71
4489	0.28	1	9	0	10.98	-10.88	11.5	5.68	18.32	1.8	114.95
4450	0.24	1	9	0	10.58	-11.17	11.5	5.69	19.08	1.78	114.33
4344	0.25	1	24	0	10.58	-11.31	11.85	6.48	17.94	1.76	114.33
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Last edited by ohm; 01-19-2010 at 02:20 PM.
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Old 01-16-2010, 10:44 PM   #2
subiewrx001
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water/meth, spt intake

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do you have a front mount intercooler? if you dont those AFRs seem a little lean at WOT
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Old 01-16-2010, 10:49 PM   #3
dan az
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knock at that high a load and rpm I would be concerned about, and yea 11.6 is pretty lean for me.
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Old 01-16-2010, 10:51 PM   #4
ohm
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IAG Built

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Quote:
Originally Posted by subiewrx001 View Post
do you have a front mount intercooler? if you dont those AFRs seem a little lean at WOT
Nope. I am running an APS TMIC.

I should add that I am running 93oct and 50/50 meth.
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Old 01-17-2010, 09:45 AM   #5
ohm
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With meth an AFR of 11.6 would be considered acceptable.

Another 3rd-4th-5th log with negative KC only in 3rd gear. Knock Learning is clean at 0, and DAM is 1.


Code:
RPM	Load	DAM	IADV	KC	KL	TP	Boost	AFR	IDC	MAF	MAFV	VS
2282	1.68	1	17.5	-1.4	0	99.96	2.03	13.11	12.41	64.64	2.54	25.48
2413	1.83	1	16.5	-1.4	0	99.96	3.05	12.31	13.54	74.81	2.72	26.72
2528	2.04	1	16	-1.05	0	99.96	4.21	12.65	15.8	83.46	2.78	27.96
2693	2.16	1	16	-1.05	0	99.96	5.51	12.77	18.59	101.12	2.98	27.96
2819	2.4	1	16.5	-1.05	0	99.96	7.25	12.65	20.85	113.94	3.14	30.45
3017	2.58	1	17	-0.7	0	99.96	9.86	12.88	24.84	135.88	3.44	32.93
3248	2.89	1	16	-0.7	0	99.96	13.78	11.39	37.78	164.03	3.64	32.93
3523	3.56	1	14.5	-0.7	0	99.96	20.45	11.15	48.28	232.98	4	36.66
3961	4.24	1	15	-0.35	0	99.96	22.34	11.15	59.63	294.28	4.22	40.39
4321	4.11	1	16	-0.35	0	99.96	22.34	11.15	62.53	303.12	4.28	40.39
4705	3.99	1	17.5	-0.35	0	99.96	22.34	11.15	65.86	314.64	4.32	45.36
5026	4.1	1	18.5	0	0	99.96	22.34	11.15	71.86	343.21	4.48	51.57
5357	4.07	1	19.5	0	0	99.96	22.34	11.15	77.18	363	4.54	51.57
5727	3.94	1	20	0	0	99.96	22.34	11.15	78.08	380.96	4.68	57.79
6015	3.83	1	21	0	0	99.96	22.34	11.15	78.65	391.21	4.64	64.62
6337	3.7	1	22.5	0	0	99.96	22.34	11.15	80.16	380.31	4.68	70.21
6624	3.55	1	23	0	0	99.18	22.34	11.15	78.57	381.59	4.6	70.21
5750	0.21	1	27	0	0	16.46	-7.98	11.39	7.41	35.35	2.22	75.81
5215	2.55	1	19.5	0	0	99.96	14.5	11.85	59.31	281.31	4.24	78.91
5152	4.32	1	19	0	0	99.96	22.34	11.15	81.77	377.1	4.62	78.91
5479	4.05	1	19.5	0	0	99.96	22.34	11.15	76.04	376.46	4.62	82.02
5570	3.99	1	19.5	0	0	99.96	22.34	11.15	76.72	352.14	4.58	85.13
5717	3.97	1	20	0	0	99.96	22.34	11.15	76.59	371.96	4.62	85.13
5842	3.87	1	20.5	0	0	99.96	22.34	11.15	77.46	371.32	4.58	88.86
6033	3.83	1	21	0	0	99.96	22.34	11.15	78.2	368.76	4.66	92.58
6164	3.75	1	21.5	0	0	99.96	22.34	11.15	78.01	374.53	4.62	96.31
6283	3.63	1	22	0	0	99.96	22.34	11.15	78.6	373.24	4.64	96.31
6445	3.59	1	22.5	0	0	99.96	22.34	11.15	79.47	372.6	4.62	100.66
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Old 01-19-2010, 02:26 PM   #6
ohm
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Just an update after doing a bit of research on what exactly could be causing the -KC, which could be any number of things. A few posts that I read pointed towards the MAF sensor being dirty that would contribute to some poor performance, and -KC being triggered. I figured what the hell, so I checked to see how dirty it was, and sure enough it was caked with black grim after 30k miles. The IAT probe was especially dirty, so I cleaned it up real good, then did some datalogging. To my surprise the logs were clean, no -KC existed at all. I will be monitoring the next few days to see if cleaning the MAF really helped fix the problem for good.

3rd gear log

Code:
RPM	Load	DAM	IADV	KC	KL	TP	Boost	AFR	IDC	MAF	MAFV	VS
2196	1.12	1	35.5	0	0	26.66	-1.16	14.84	8.93	47.85	2.34	25.48
2267	1.33	1	28	0	0	34.5	0.58	13.57	11.74	52.7	2.48	26.1
2376	1.49	1	23.5	0	0	34.5	1.16	11.5	12.33	60.73	2.56	27.34
2496	1.61	1	20	0	0	39.98	2.03	12.31	13.44	70.48	2.7	27.34
2630	1.97	1	16	0	0	99.96	4.21	12.31	16.48	89.72	2.84	28.58
2799	2.17	1	16	0	0	99.96	5.66	12.53	19.18	105.99	3.02	31.07
2935	2.42	1	16	0	0	99.96	7.69	12.53	21.95	117.07	3.2	31.07
3144	2.57	1	16.5	0	0	99.96	10.73	12.99	26.48	141.02	3.38	32.93
3372	3.04	1	15	0	0	99.96	14.79	11.5	37.67	178.75	3.72	36.04
3700	3.71	1	14.5	0	0	99.96	22.48	11.15	51.39	243.72	4.12	36.04
4049	4.13	1	14.5	0	0	99.96	22.48	11.15	60.24	291.24	4.34	39.15
4443	4.1	1	16	0	0	99.96	22.48	11.15	62.34	312.81	4.32	44.12
4806	4.03	1	17	0	0	99.96	22.48	11.15	67.11	326.4	4.38	49.71
5125	4.05	1	18	0	0	99.96	22.48	11.15	73.14	359.14	4.58	49.71
5516	4.01	1	19	0	0	99.96	22.48	11.15	75.85	368.74	4.6	55.92
5803	3.84	1	20	0	0	99.96	22.48	11.15	77.36	380.95	4.64	62.14
6136	3.73	1	20.5	0	0	99.96	22.48	11.15	78.8	382.88	4.62	62.14
6384	3.6	1	21.5	0	0	99.96	22.48	11.15	79.2	388.01	4.6	68.35
5909	1.03	1	-15.5	0	0	11.37	-6.82	11.61	12.38	18.99	1.64	73.94
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